Situational awareness: what is happening, what it means, what comes next

The standard model comes from Mica Endsley’s 1995 paper in the journal Human Factors. It describes three levels that build on each other:

• Perception. Noticing the facts that matter: the river is at 2.1 m, Team 3 has stopped moving.
• Comprehension. Working out what they mean together: the low road will be cut, and Team 3 is on the far side.
• Projection. Looking ahead: in about an hour that team has no way back unless it moves now.

A common operational picture is a shared display of information. Situational awareness is what a person makes of it. Two commanders can look at the same map and reach different conclusions, and a beautiful picture does nothing for someone who has not looked at it for an hour. The picture supports level one for everyone at once; levels two and three depend on training, experience and talking to each other.

The UK’s JESIP joint doctrine adds the shared version: shared situational awareness is a common understanding of the circumstances, consequences and implications of an emergency, along with an appreciation of what each organisation can do and what its priorities are. It is one of the JESIP principles for joint working, and an M/ETHANE message is a common way to start it.

At a flood, the control room sees a gauge cross a threshold (perception). The tactical commander knows that level closes the only bridge (comprehension) and asks where the evacuation buses are, because they need to cross in the next 40 minutes (projection). Knowledge of the ground supplied the rest, which is why the KNOW and EXECUTE stages of the preparedness cycle depend on each other.